Fuel cap gaskets

I read the past article on gas caps and purchased the new gaskets from Aircraft Spruce. I removed the screws then took off the old gasket that was not rubber. I placed the new gasket on the brass backing plate and reassembled the cap. With the thicker rubber gasket I find they are too tight of a fit and very difficult to turn and secure. I tried lubricating them with Dow Corning 4 dialetric grease but still too hard to turn the final twist to lock into position. I then shimmed out the cap with a couple of washers but the fit was too loose to seal the tank opening. I’ll try replacing the washers with a round piece of thin aluminum to match the shim that is under the cap. The shim thickness is critical to being able to secure the cap. Also I am not happy how loose and floppy the new gaskets fit the cap. Is anybody else having issues with new gas cap gaskets?

Comments

  • Hi, and yes. There are two thicknesses and I purchased the too-thick ones, also, to the same end as you. Get the thinner ones and they snap right on. You don't have to remove the screws, they just stretch and pop on.

    Scott Sherer
    Wright Brothers Master Pilot, FAA Commercial Pilot
    Aviation Director, Piper Owner Society Forum Moderator and Pipers Author.

    Need help? Let me know!

  • Scott,

    Are the correct gaskets the 1/16 inch type? (A/C Spruce # 05-18500)

    Jim Torley
    CFI-A/I/G
    1969 Arrow 200
    Based at KFLY (Colorado Springs, CO)

  • There are two correct gas caps for the Arrow. One is the 66817-00 cap and it uses the 66815-00 thin gasket, listed as 05-18500 on aircraft spruce. The other is the 39830-800 cap and it uses the 39829-00 thick gasket.

    Scott Sherer
    Wright Brothers Master Pilot, FAA Commercial Pilot
    Aviation Director, Piper Owner Society Forum Moderator and Pipers Author.

    Need help? Let me know!

  • Thanks, Scott. I will check which is the correct one for my Arrow.

    Jim Torley
    CFI-A/I/G
    1969 Arrow 200
    Based at KFLY (Colorado Springs, CO)

  • Thanks Scott. I will look for the thin fuel cap gaskets. Thanks for your help.
    Cliff Speare

  • Ok Cliff. Good luck!

    Scott Sherer
    Wright Brothers Master Pilot, FAA Commercial Pilot
    Aviation Director, Piper Owner Society Forum Moderator and Pipers Author.

    Need help? Let me know!

  • I received my two gaskets yesterday from Aircraft Spruce. Too cold to mess with them today and snow forecast for the next 2 days.

    Jim Torley
    CFI-A/I/G
    1969 Arrow 200
    Based at KFLY (Colorado Springs, CO)

  • Hi Jim,
    Glad to hear that you've received them. Don't remove the screws on the cap, they just snap on and off. :)

    Scott Sherer
    Wright Brothers Master Pilot, FAA Commercial Pilot
    Aviation Director, Piper Owner Society Forum Moderator and Pipers Author.

    Need help? Let me know!

  • I took one gasket off a cap to measure the inside and outside diameters and it was trivial to take off so I suspect the new ones will be a non-issue. I also got a small container of the "lube" just to preserve the gasket life. It is likely that my home base airport will be closed for upwards of 3 months this summer during which the one and only runway of consequence will be re-built thus leading me faced with moving to the municipal aerodrome (KCOS) and having to tie down outside (AUGH!). Hence my ordering new gaskets to keep rainwater out of the tanks.

    Jim Torley
    CFI-A/I/G
    1969 Arrow 200
    Based at KFLY (Colorado Springs, CO)

  • Good idea, Jim. Sorry about your home airport being closed. Can't they do that in January? lol :)

    Scott Sherer
    Wright Brothers Master Pilot, FAA Commercial Pilot
    Aviation Director, Piper Owner Society Forum Moderator and Pipers Author.

    Need help? Let me know!

Sign In or Register to comment.